WASHINGTON, December 19, 2000 (GulfLINK) - Information gained from more recent investigations and research into the use of depleted uranium has prompted the special assistant for Gulf War illnesses to release an updated version of the Department of Defense's environmental exposure report on depleted uranium in the Gulf War. The additional information supports previous assessments that depleted uranium is not the cause of the illnesses some Gulf War veterans are experiencing.

The report originally released in 1998 explains that the first battlefield use of depleted uranium in tank armor and armor-piercing ammunition took place during the Gulf War. Military experts say that depleted uranium weapons and armor contributed to the overwhelming success of coalition forces during the Gulf War. But after the conflict, some veterans expressed concern about the chemical toxicity and radiological properties of depleted uranium and possible health risks from its use.

The report examines the issues regarding depleted uranium exposures during and after the Gulf War and includes an explanation of depleted uranium's properties. Depleted uranium is a by-product of the process for converting natural uranium into the enriched form used in nuclear weapons and reactors. What remains after the process, the depleted uranium, is 40 percent less radioactive than natural uranium. Depleted uranium is a toxic heavy metal. David Case, Ph.D., of the special assistant's environmental and occupational exposure team, says the health risks from its radioactivity are slight compared to the heavy metal toxicity risk.

"Exposure to depleted uranium can cause kidney problems because of its heavy metal toxicity," Case said. "The exposure that could cause radiation-related health problems is thousands of times more than the exposure that could cause heavy metal toxicity symptoms."

The updated environmental exposure report contains references to more recent information as presented in RAND's "Review of the Scientific Literature as it Pertains to Depleted Uranium." Other sources have also contributed to a better understanding of depleted uranium's effects.

"We also have a very important document put out by the Agency for Toxic Substances and Disease Registry," said Case. "The ATSDR is charged with summarizing and informing the public about the health effects of hazardous substances."

Those profiles describe the toxicity of a substance over time. The ATSDR report on uranium focuses on the chemical toxicity of natural uranium, which is the same as that of depleted uranium. It also discusses how common natural uranium is, which is important when examining the effects DU may have on the environment.

"People who hear about the 320 tons of DU fired in the Gulf War have been led to believe that the DU could cause serious environmental problems, but the ATSDR report helps put it into perspective," said Case. "They report there are normally two to four tons of uranium in the top foot of soil per square mile."

The primary hazard associated with uranium is due to its chemical properties, not its radiological properties. ATSDR cites that "no human cancer of any type has ever been seen as a result of exposure to natural or depleted uranium" and further states that because of the low radiation from natural and depleted uranium, "no radiological health hazard is expected from exposure to natural or depleted uranium."

Case says the ATSDR report adds credibility to DoD's environmental exposure report because it provides a thoroughly peer-reviewed evaluation of uranium by an independent agency outside the Defense Department. In addition, the Institute of Medicine recently released a report that supports the environmental exposure report's conclusions. In "Gulf War Health, Volume I: Depleted Uranium, Sarin, Pyridostigmine Bromide, and Vaccines," the IOM reported its comprehensive assessment of the scientific literature available on four potentially harmful agents.

In its review of depleted uranium, the committee concluded "there is limited/suggestive evidence of no association between exposure to uranium and clinically significant [kidney] dysfunction."

The IOM also found inadequate evidence to determine whether an association does, or does not, exist between uranium exposure and other health outcomes. Citing information from studies of uranium processing workers and case reports of workers accidentally exposed to large doses of uranium compounds, the committee wrote, "While the studies did not suggest that uranium has adverse health effects, the studies were of insufficient quality, consistency, or statistical power to permit a conclusion regarding the presence or absence of an association in humans,"

The revised environmental exposure report also updates the findings of the Department of Veterans Affairs study currently under way at its medical center in Baltimore, Md. Since 1993, the VA has monitored 33 Gulf War veterans who were seriously injured in friendly-fire incidents involving depleted uranium. Many of these veterans continue to have medical problems, mostly relating to the injuries they received during friendly-fire incidents. About half of this group still have depleted uranium metal fragments in their bodies. These veterans are being followed very carefully and a variety of medical tests are being done to determine if the depleted uranium fragments are causing any health problems.

So far, published results indicate the veterans who were in friendly-fire incidents have not experienced health problems related to their exposure to depleted uranium. Tests for kidney function have all been normal for veterans in the program. In addition, the reproductive health of this group appears to be normal in that no babies born to these veterans between 1991 and 1997 have exhibited birth defects.

"Overall, the medical news is good news," said Case. "But we're not stopping our work and Veterans Affairs plans to keep its investigations open, and continue to monitor those individuals."

The revised environmental exposure report also updates the Gulf War exposure assessments. Originally, the special assistant's office divided Gulf War exposures into three categories, Level I - involving around 170 servicemembers - being the highest level of exposure. The General Accounting Office criticized the original estimates, prompting the special assistant's office to take a closer look. These were re-examined by the U.S. Army Center for Health Promotion and Preventive Medicine staff who reevaluated the DU exposure Gulf War veterans may have received and the possible health risks.

"Modeling is not an exact science," Case continued. "It was difficult to interpret the exposure data because we didn't have a lot of it. The revised exposure estimates are still conservative." We are also sponsoring an expanded test-firing program, which is currently underway, to provide a full understanding of DU's health and safety characteristics in combat vehicles.

The updated estimates indicate that Level II and Level III exposure were far below any applicable safety guidelines. The assessments by CHPPM - together with the results of the medical follow-up program, and the work performed by RAND, the ATSDR and the IOM - form a body of consistent evidence indicating that depleted uranium exposures are not the expected cause of Gulf War veterans' illnesses.

This version of the report is an interim report. The final environmental exposure report on depleted uranium will be published when DoD is satisfied that the health risks involved have been thoroughly evaluated by the results from the live test-fire program. The Armed Forces Radiobiology Research Institute and the Lovelace Respiratory Research Institute are continuing their research on the effects of imbedded depleted uranium fragments. Also, several laboratories are testing uranium levels in the urine of veterans, and common standards are being sought so the results of those tests can be compared. And, the VA will continue their medical surveillance programs for Gulf War veterans.

The entire environmental exposure report can be read on GulfLINK. Case emphasized that this is an interim report. We encourage anyone with information that might impact its findings to contact the office by phone at (800) 497-6261 or by e-mail at brostker.osd.mil.